Philip Seymour Hoffman’s autopsy is inconclusive and further tests are needed to determine why the actor died, the New York City Police medical examiner’s office said Wednesday. Hoffman died on Sunday, at age 46, of what many assumed to be a heroin overdose, but the coroner now has to run more tests, the Associated Press reports.

Medical examiner spokeswoman Julie Bolcer said there is not yet a timetable for when further tests will be completed. While awaiting results, police continue to investigate the incident as a suspected drug overdose.

Hoffman was found unconscious on the bathroom floor of his Manhattan apartment Sunday morning with a syringe needle still in his arm. Police reportedly discovered roughly 50 bags of heroin, used syringes, and other drug paraphernalia in his apartment. He’d last been seen at 8 p.m. on Saturday and had missed an appointment to pick up his three children Sunday morning, ABC News reports.

“We are devastated by the loss of our beloved Phil and appreciate the outpouring of love and support we have received from everyone,” Hoffman’s family said in a statement. “This is a tragic and sudden loss and we ask that you respect our privacy during this time of grieving. Please keep Phil in your thoughts and prayers.”

Hoffman, whose extraordinary talent and artistic versatility made him among the most beloved actor/directors of his generation, was publicly candid throughout his career about his struggle with addiction. He stopped using drugs in his early 20s and remained clean for more than two decades before relapsing and checking into rehab last year.

“I saw him last week, and he was clean and sober, his old self,” David Bar Katz, the friend who found Mr. Hoffman Sunday, told the New York Times. “I really thought this chapter was over.”

Oscar-nominated three times for supporting roles, Hoffman won an Academy Award for Best Actor as the leading man in the 2005-film Capote. Over the course of his truncated career, he appeared in more than 50 films while acting and directing on and off Broadway. At the time of his death, Hoffman was in the final stages of working on The Hunger Games: Mockingjay parts 1 & 2, set for release in November this year and November 2015, respectively.